We professional historians must await further evidence before fully answering those questions, a process that typically requires decades. In the nearer term, Trump’s well-documented ignorance of history offers a more reasonable explanation for his unprecedented deployment of trust in a relationship in which so many others counsel caution. Perhaps he simply does not know the real history of Russian-American relations since 1991. Perhaps he is unaware of Putin’s record. This short explanation of trust’s place in Russian-American relations since the Cold War can explain Vladimir Putin’s systemic distrust of American promises. It cannot explain Trump’s reasons for trusting a man no other Western leader would.